This code lets you erase a previously locked (and thus in-accessible) Multi-Media Card, making it useful again.
Sorry there isn't much documentation, but the comments should be helpful. Used the serial port for all comms, can be made standalone though.
I wrote it to run on the STK500 (but can be used w/any AVR with enough pins), just plugged the card to the pin headers for PortC, and put some cards to make it thicker/hold it in place between the pins.
Added some (blurry) pictures and reduced COM port speed